With the rapid development of the communications industry, needs for information services constantly increase. To meet the growing user needs, network operators need to add more devices. However, due to limited installation space in an equipment room, density of communications devices is becoming higher, the size of the devices is becoming smaller, but power of the devices is becoming higher. Therefore, how to resolve a problem of ventilation and heat dissipation for a compact device of high power consumption becomes an urgent problem to be resolved in design of a communications device.
At present, a communications device generally includes multiple communications boards, and the communications boards are inserted into slots disposed on a backplane in a cabinet. Because the size of the cabinet is becoming smaller, and an integration level of the communications device is becoming higher, the problem of ventilation and heat dissipation for the communications device becomes one of bottlenecks in board subrack design. In the prior art, conventional air cooling is adopted for a communications device. That is, a running communications device is cooled by using a fan. For air-cooled heat dissipation, an air exhaust problem is involved, and heat is dissipated for the communications device often in a manner in which air flows in from the front and flows out from the rear or air flows in from the front and flows out from the bottom. However, neither air flowing out from the rear nor air flowing out from the bottom helps heat dissipation of an entire equipment room. Consequently, the heat dissipation efficiency of the entire equipment room is relatively low.